Safety appliance



S. MYERSON Dec. 24, 1940.

SAFETY APPLIANCE Filed March 9, 1939 2 Sheets-Sheet 1 IIIIIIIII'IIIIIIIZ III mam 6719070 3 @zyj/ Dec. 24, s, MYERSQN i 2,225,708

SAFETY APPLIANC E Filed March 9, 1939 I 2 Sheets-Sheet 2 Patented Dec. 24, 1940 UNITED STATES SAFETY APPLIANCE Simon Myerson, Brookline, Mass.

Application March 9,

Claims.

This invention relates to safety appliances for attachment to machines and to machines provided with such appliances. More particularly,

the present invention provides a safety appli- 10 moving ram or the like.

While the present invention is applicable to a wide variety of machines, for convenience of description and illustration the invention will hereinafter be particularly referred to as applied to punch presses, it being understood, however, that the invention may be employed generally with machines of the type which have reciprocatory rams or the like in cooperating relation with a bed, such as die stamping machines, punch presses, and the like.

The present invention particularly provides safety appliances of very simple construction and having the minimum number of essential parts which may be easily secured to punch presses or the like.

The principles of the present invention may be employed either with a press of the footactuated type or with a power-operated press. In either case my safety appliance comprises asimple bar which may conveniently be formed of strap metal and which need be secured by only two screw-threaded fastening elements or rivets to the frame of the machine. may conveniently provide a support for a simple locking member in the form of a lever having an intermediate portion pivotally mounted on the bar and having one end portion which provides a handle while the opposite end portion may provide a part fixed in relation to the body portion of the lever and preferably integral therewith, which affords an abutment or blocking part normally positioned in the path of a control member whose movement is essential to the operation of the reciprocatory member or ram of the machine. The lever may be arranged so that it is yieldably held in normal position to block movement of the control member. For this purpose one end of the lever may be weighted or a spring may be provided.

When a device of this character is employed on a press of the foot-operated type, it is desirable to arrange two similar levers on the supporting bar with spaced, oppositely movable handles so that both hands of the operator mustbe employed to actuate the levers in order to permit The bar 1939, Serial No. 260,733

operation of the machine. The levers of this appliance may have body portions in the form of straight, flat metal bars extending beneath the bed of the machine and providing upstanding handles at their forward ends. The rear ends of the levers may have integral hooked portions which are ;normally held in juxtaposition to block the path of a swinging control member which must move when the reciprocatory ram or the like is actuated.

Preferably the hooked portions of the levers may provide beaks having oppositely inclined surfaces which are normally juxtaposed and which engage a recess in the control member of the machine, the recess providing surfaces which incline toward each other and which cooperate with the complementary surfaces of the beaks in such a manner that tendency of the control member to move to cause actuation of the press results in a wedging engagement of the parts and the more firm maintenance of the hooked portions of the levers in their blocking positions. Thus an arrangement is provided which positively prevents the movement of the control member in such a manner as to dislodge the blocking parts from their normal positions.

When an appliance of the present type is employed on a press of the power-operated type, it may conveniently be associated with the control mechanism for the one-revolution clutch of such a press. Such a control mechanism ordinarily includes a manually swingable control member at one side of the machine which is actuated by one hand of the operator to cause the main shaft of the machine to be rotated through one revolution to cause'one downward movement of the ram and a corresponding upward movement thereof.

In accordance with this invention, a simple safety appliance is provided which requires actuation by the other hand of the operator of the machine before the clutch mechanism can be manually actuated. Such a safety appliance. comprises a supporting bar providing bearings for the transversely extending portion of a lever, which has a handle at the side of the machine remote from the clutch-actuating mechanism, but which provides a blocking part to engage a clutch controlling member and to prevent movement of the same as long as the lever is in normal position. The lever may be swung from this normal position upon engagement, for example, by the left hand of the operator of the machine, thereupon to permit actuation of the one-revolution clutch mechanism by the right hand of the operator of the machine.

In the accompanying drawings: Fig. 1 is a side elevation, somewhat diagrammatic in character, of a punch press having my improved safety appliance applied thereto, parts being broken away and shown in section;

Fig. 2 is a section on line 2--2 of Fig. 1, a part being broken away and parts shown in section and in dotted lines;

Fig. 3 is an enlarged view of portions of the levers of the safety device and the cooperating portion of the control member;

Fig. 4 is a front elevation of a power-operated press having an improved safety appliance applied thereto in accordance with the teachings of the present invention;

Fig. 5 is a side elevation of a portion ofthe press shown in Fig. 4; and

Fig. 6 is a rear elevational detail of my improved appliance and certain cooperating parts of the machine.

Figs. 1, 2 and 3 show a safety appliance constructed in accordance with the present invention and applied to a punch press of the footoperated type. Such a press may comprise a frame I providing a horizontal bed 2 and an upstanding portion 3 providing a head 4 in which a reciprocatory ram 5 is slidably mounted. A large swinging control member 6 has a pivotal mounting 1 on the upstanding portion 3 of the frame and has its lower end fixed to a bar 9 extending inwardly from an actuatingpedal Hi. It is to be undertsood that the machine so far described is merely disclosed by way of illustrationand that safety appliances of the type shown herein may be applied to machines of this general type which, however, differ widely in design.

My improved safety device,which is shown in 40 Figs. 1, 2 and 3, includes a transverse supporting bar II which may conveniently be formed of heavy strap metal and which is secured by two screw-threaded fastenings I2 beneath the bed 2 of the machine. Suitable spacers l4 are 45 disposed between the bar I I and the bed so that the bar is disposed somewhatbelow the latter.

The intermediate portion of the bar may be provided with pivotal mountings l5 for swinging levers l6 which are disposed between the bar ll 50 and the bed 2 of the machine. The body portions of the levers I6 may each consist of but a single, flat bar of metal, the forward ends of the levers, however, each being provided with an upstanding handle I1. 55 of the levers may provide integral hook-like portions having flat, juxtaposed surfaces which may normally be pressed into engagement behind the member 6, as shown in Figs. 2 and 3.

As shown particularly in Fig. 3, the hook-like 60 portions of,the levers I6 may be provided with beaks'lB having surfaces inclining inwardly and forwardly toward the substantially central vertical plane of the control member 6. The latter is provided with a recess l9 having surfaces in- 65 clined inwardly toward each other and toward the front of the machine. Tension springs 20 may conveniently be connected to portions of the levers l6 which are in front of the pivots l5 and to fixed parts of the machine so that the springs 70 tend to press the cooperating surfaces, of the hooked end of the levers toward each other and; to hold the beaks l8 in juxtaposition. Preferably the springs 20 may be connected to lugs 22 which areheld in place by the fastening ele- ZE mentsl2.

The rear extremities When the operator desires to cause operation of the machine shown in Fig. 1, he depresses the pedal I0 with his foot. However, should either one or both of the levers l6 be in normal position, the tendency of the lower part of the lever B to swing rearwardly will cause recess H! to engage the beak or beaks l8 of the'lever or levers so that a firm locking engagement of these parts is assured and so that the control member 6 cannot swing a lever about its pivot l5 and out of the path of that member. In order to permit operation of the press, the operator must engage both of the handles H with his hands, moving these handles in opposite directions, i. e., toward each other, and thus necessarily having-his hands out of the path of the downwardly moving ram or die.

The form of the invention shown in Figs. 4, 5 and 6 is particularly useful with presses of the power-operated type, and especially such presses which have a conventional one-revolution clutch. For purposes of illustration I have shown such a press in Fig. 4, which comprises a frame 3| including a bed 32 and an upstanding portion 33 providing vertical guideways for a reciprocatory ram 34. The press is provided with a belt-operated pulley 36 or the like and with a one-revolution clutch mechanism 37 through which the power received from the constantly rotating pulley 36 may be efiective in causing one revolution of the main shaft 38 of the press and one downward and one upward movement of the ram 34. The clutch mechanism 31 may ordinarily be arranged to be actuated by a link 42 connected to a, swinging control member 44 having a depending handle 45 at one side of the machine. When the handle 46 is swung upwardly and forwardly, the link 42 is effective in causing engagement of the clutch mechanism 31 and consequent reciprocatory movement of the ram.

In order to prevent such operation of the control member 34, when one hand of the operator may be in the path of the downwardly movable die, I have provided a safety appliance of the type disclosed herein. Such an appliance may comprise a supporting bar 50 formed of strap metal and having a generally U-shaped form, the b ight portion of the bar being provided with two openings to receive screw-threaded fastening elements 52 at the front of the machine. The legs of the U-shaped bar 50 preferably extend rearwardly at opposite sides of the upstanding portion 33 of the frame of the machine and the rearmost extremities'of these legs provide bearings for the transversely extending portion 54 of a lever 55.

At the side of the machine remote from the clutch-controlling mechanism, the lever preferably is provided with a section 56 which extends forwardly from its portion 54 and with a downward extension 5'! of this section which affords a handle at the front of the machine and at the side thereof remote from the handle 46. The opposite end of the lever has a lug 58 fixed thereto, as for example by welding, and normally positioned to block the downward movement of the rear end of the control member 44. The sections and 51 of the lever 55 afford sufiicient weight forwardly of the pivotal axis of the lever so that the lug 58 is normally held in this position, providing a flat surface which engages a corresponding lower surface of the rear part of the control member 44, the parts being arranged so that the lever 55, as viewed in Fig. 5, cannot swing in a clockwise direction beyond this position, since the member 4-4 acts as a stop for the member 58.

'With an appliance of this character, actuation of the clutch mechanism by the handle 44 is impossible unless the lever 55 is moved out of its normal position. If the handle 51 is moved upwardly and forwardly at the same time as the handle 46 or prior to such movement of the handle 45, the clutch mechanism may then be actuated in the normal manner. Such actuation of the handles 4.6 and 51 requires the hands of the operator to be remote from each other and remote from the bed of the machine.

It is evident that the present invention provides safety appliances of very simple type applicable either to foot-operated or power-operated presses so that both hands of the operator of such a press must be spaced away from the bed of the machine when the ram moves downwardly. Each of these safety appliances is provided with a simple swinging lever having a blocking part fixed relative to the body portion of the lever and normally effective to block the swinging movement of a control member of the press. Each of these appliances also may be secured to the frame of the machine by only two fastening elements and each appliance may conveniently comprise but a single supporting bar with openings near its ends to receive such fastening means. It therefore is evident that I have provided very simple, dependable and effective safety appliances for presses, stamping machines and the like.

It should be understood that the present disclosure is for the purpose of illustration only and that this invention includes all modifications and equivalents which fall within the scope of the appended claims.

I claim:

1. In combination with a machine of the class described which includes a frame providing a bed, a ram in cooperating reciprocatory relation to said bed, and a control part, the movement of which is essential to cause movement of the ram, a safety appliance comprising a bar attached in fixed transverse relation to the machine, a lever having a direct pivotal connection with the bar, said lever having a handle at one end and being provided with an abutment fixed thereto at its end remote from the handle, said abutment being positioned directly to block the movement of the control part, said lever being movable pivotally of said bar to move the abutment out of its normal blocking position.

2. A safety appliance for a machine of the type which includes a reciprocatory ram and a control part whose movement is essential to cause movement of the ram, said appliance comprising a supporting bar to be secured in fixed transverse relation to said machine, a manually actuable lever pivotally mounted on said bar, said lever having a handle at one end and an abutment fixed to its opposite end and in the normal position of the lever disposed in the path of said control part to block movement thereof, said lever being yieldably held in said normal position, but being manually movable pivotally of said bar out of such position to permit operation of the machine.

3. A safety appliance for a machine of the type which includes a reciprocating ram and a swinging control member whose movement is essential to cause movement of the ram, said appliance comprising a supporting bar for attachment to the frame of th machine, a pair of levers having intermediate portions pivotally mounted on the bar, each lever having a, handle at one end and providing a blocking part in fixed relation to the body of the lever at its end remote from the handle, the blocking parts of said levers normally being positioned in contact with each other to prevent the swinging movement of said member, springs to hold the levers in their normal positions, said levers being manually swingable against the influence of said springs to separate their blocking parts and move them away from the control member.

4.. A safety appliance for a machine of the type which includes a reciprocating ram and a swinging control member whose movement is essential to cause movement of the ram, said appliance comprising a supporting bar for attachment to the frame of the machine, a pair of levers havingintermediate portions pivotally mounted on the bar, each .lever having a handle at one end and providing a blocking part in fixed relation to the body of the lever at its end remote from the handle, the blocking parts of said levers normally being positioned in contact with each other to prevent the swinging movement of said member, springs to hold the levers in their normal positions, said levers being manually swingable against the influence of said springs to separate their blocking parts and move them away from the control member, the blocking parts of each of said levers being of hook-like form, the control member being recessed to receive each of the hook-like portions of the levers and arranged so that tendency of the control member to swing in a direction essential to operation of the ram may cause a tightened engagement of the blocking part of each lever therewith.

5. A safety appliance for attachment to a machine of the type having a frame including a bed and having a ram in reciprocatory relation to the bed as well as a swinging control memberwhose movement is essential to the reciprocatory movement of the ram, said appliance comprising a supporting bar for attachment to the frame of the machine, a pair of levers having intermediate portions pivotally connected to said bar, each lever providing an integral hooked end portion normally disposed in a position to block the swinging movement of the control member, the opposite end of each lever providing a manually actuable handle, springs for urging the hooked portions of the levers in juxtaposition, said hooked portions of the levers providing beaks with oppositely inclined surfaces to engage a recess of complementary form in the control member, said beaks and said recess being arranged so that tendency of the controlling member to move in a manner essential when the operation of the ram is effected causes said parts of the levers to be more firmly pressed together and pressed into engagement with the control member, said handles being arranged so that said levers may be swung from their normal positions to move the beaks out of the path of the control member.

6. A safety appliance of the class described for attachment to a machine of the type having a frame including a bed and having a ram in reciprocatory relation to said bed as Well as having a swinging control member whose movement is essential to the reciprocatory movement of the ram, said appliance comprising a flat metal bar having two openings to receive fastening bolts whereby the bar may be secured in fixed relation to the frame of the machine beneath the bed' thereof, said bar providing a pair of pivotal mountings spaced inwardly from said openings, a pair of levers supported respectively by said mountings, the corresponding ends of the levers at one side of the bar providing hook-like portions with normally juxtaposed beaks to engage a recessed portion of the control member, the opposite ends of the levers providing handles, springs connected to said levers between the pivotal mountings and the handles, and in the normal position of the parts eifective to urge the hooked portions of the levers into juxtaposition, said levers being manually actuable to move said hooked portions apart thus to move said portions out of the path of the swinging control member. 7

7. A safety appliance for attachment to a machine of the class described having a frame including a bed and having a reciprocatory ram in cooperating'relation with said bed as well as having a clutch and a movable control member therefor, said appliance comprising a bar for attachment in fixed relation to the frame of the machine, a lever, said bar providing a pivotal mounting for the lever, said lever and bar having portions arranged to extend transversely of the frame of the machine, the lever providing a handle at one side of the machine and having an abutment fixed thereto at the opposite side of the machine, said abutment being positioned normally to lie in the path of the control member and block movement of the same, said abutment being swingable out of said position upon manual actuation of the lever pivotally of the bar by one hand of the operator of the machine.

8. A safety appliance for attachment to a machine of the class described having a frame including a bed and having a reciprocatory ram in cooperating relation with said bed as well as mountings for the lever, said lever and bar having portions arranged to extend transversely of the frame of the machine, the lever providing a handle at one side of the machine and having an abutment fixed thereto at the opposite side of the machine, said abutment being positioned normally to lie in the path of the control member and block movement of the same, said abutment being swingable out of said position upon manual actuation of the lever pivotally of the bar by one hand of the operator of the machine, the end of the lever which provides the handle having a weight distribution efiective to hold said abutment in its normal position.

9. A safety appliance for attachment in fixed relation to amachine of the type including a frame and a reciprocatory ram, as well as a clutch having a manually movable control member, said appliance including a supporting bar of generally U -shaped form, the legs of the bar providing bearings, a lever having a transverse portion extending through said bearings and having a handle at one end disposed outwardly of the corresponding leg of the U-shaped bar, the opposite end of the lever supporting an abutment adapted normally to be positioned in blocking relation to the clutch controlling member, said lever being swingable out of its normal position pivotally of the bar to permit manual actuation of the clutch controlling member.

10. A safety appliance for attachment in fixed relation to a machine of the type including a frame and a reciprocatory ram, as well as a clutch having a manually movable control member, said appliance including a supporting bar of generally U-shaped form, the legs of the bar providing bearings, a lever having a transverse portion extending through said bearings and having a handle at one end disposed outwardly of the corresponding leg of the U-shaped bar, the opposite end of the lever supporting an abutment adapted normally to be positioned in blocking relation to the clutch controlling member, said lever being swingable out of its normal position pivotally of the bar to permit manual actuation of the clutch controlling member, the handle portion of the lever comprising a section thereof extending substantially parallel to the corresponding leg of the U-shaped bar, and a depending handle portion, said section and handle portion providing suificient weight yieldably to hold the lever in its normal position.

' SIMON MYERSON. 

